Norm Dresner wrote:

First question: What is this brass trim called?

Usually "fret"

Second question: Where could I get replacement?

Relics in Witney, if you're in the UK. If you need an exact match, talk
to somewhere that does CAD-to-metal processing by either waterjet,
laser or chemical etch (etch was cheapest, last time I looked)


(Etched brass and polyester resin makes damned cheap fake Boulle work
for minimal effort)